"Pilots and technicians of Hmeymim airbase have sent their message to terrorists by priority airmail," said a caption accompanying an online post, the Daily Mail reports.
The Russian military has destroyed numerous oil facilities and tankers controlled by the Islamic State group in Syria, sharply cutting its income, defense minister Sergei Shoigu said Friday.
Russia, which has conducted an air campaign in Syria since Sept. 30, sharply raised the intensity starting Tuesday following confirmation that the Russian Metrojet plane in Egypt was downed by a bomb, which the Islamic State group said it had planted. All 224 people aboard the plane, mostly Russian tourists, were killed.
Putin has discussed cooperating on fighting IS during his meetings with President Barack Obama and other Western leaders at the sidelines of the Group of 20 rich and developing nations in Turkey this week.
French President Francois Hollande is set to travel to Washington and Moscow next week for talks on joint military action against IS, and Putin already has ordered the military to cooperate with the French.
Shoigu said the strikes this week inflicted significant casualties on IS, including more than 600 militants killed in just one strike in the province of Deir el-Zour. The claim could not be independently confirmed.
U.S. and French planes have also struck at oil targets in Deir el-Zour and elsewhere.
Putin hailed the military's performance, but added that "there is still a lot of work to do ... to rid Syria of militants and terrorists and protect Russia from possible terror attacks." Putin has ruled out Russian ground action in Syria, a position reaffirmed Friday by his spokesman, Dmitry Peskov.
The Kremlin has used the air campaign in Syria to showcase an array of new weapons, including state-of-the art cruise missiles.
On Friday, a pair of Russian Tu-160 strategic bombers flew from a base on the Kola Peninsula over the Norwegian Sea, the North Atlantic and the Strait of Gibraltar and into the Mediterranean to launch long-range cruise missiles on targets in Syria, demonstrating the Russian military's global reach.
Flights operating out of Beirut airport will continue unaffected despite a notice of planned Russian naval drills in the Mediterranean, airport official Ibrahim Abu Alioun said Friday. Lebanese national carrier Middle East Airlines said some flights to Gulf Arab states would take longer because alternative routes would be taken.
